<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script type="text/javascript">
			new Promise((resolve, reject) => resolve(1)).then(function(val) {
				console.log("第一次成功调用" + val * 2)
				return val * 2;
			}).then(function(val) {
				console.log("第二次成功调用" + val * 2)
				return val * 2;
			}).then(function(val) {
				console.log("第三次成功调用" + val * 2)
				return val * 2;
			}).then(function(val) {
				console.log("第四次成功调用")
				console.log(val);
			})
		</script>
	</head>
	<body>
	</body>
</html>
